It sounds like a joke but this is what is stated: “We are currently updating our website to reflect EPA’s priorities under the leadership of President Trump and Administrator Pruitt”. That is basically politicians reviewing what and how they want something stated. This has a familiar ring to it.
The webpage, which has been in existence for more than 20 years, explained what climate change is, what caused it and, how it affects your health, among other things. In opposition to what Trump has said in the past about climate change (he doesn’t believe it is man-made), the webpage notes many times how humans have contributed to climate change.
See http://mashable.com/2017/04/28/epa-climate-change-section-removed-trump 
Trump’s big EPA website change should make you furious
The EPA is calling it an “update.”